The halogen bulbs are generally grouped into a low-wattage (1-100 watts) single-ended halogen bulb and a high-wattage (101-500 watts) tubular double-ended halogen bulb. The single-ended halogen bulb is generally fitted into a domelike case similar to the light bulb of a flashlight or car light and is mounted in a ceiling or wall for lighting or auxiliary lighting. The tubular double-ended halogen bulb was generally used for outdoor projection and is used in recent years in the indoor floor lamp for upward projection. The high-wattage tubular double-ended halogen bulb generates heat with a low risk of explosion. In order to prevent a fire caused by a foreign object which happens to make contact with the hot halogen bulb, the tubular double-ended halogen bulb must be shielded by a protective case. It is therefore readily conceivable that a lighting fixture provided with a high-wattage tubular double-ended halogen bulb has at least two shortcomings which have to be properly addressed. In the first place, the tubular double-ended halogen bulb must be made and sold along with a protective case, thereby resulting in an increase in the cost of shipping and storage. In addition, it is almost impossible or very difficult for the consumer to replace a damaged or burn-out tubular double-ended halogen bulb.